Many factories, warehouses and supply depots utilize roller conveyors to move materials from one location to another within the facility. While some of these conveyors are gravity operated, many require power to move materials uphill or on a level grade. These conveyors are often powered by a roller chain driven by an electric motor or other power source. These roller chains must be serviced at regularly and most be replaced at regular intervals due to stretching and wear. In order to remove a roller chain or a damaged section of one, it is necessary to push out the pins that fasten the links together. Reassembling the chains is done by pushing this pin back into the links. These tasks are typically done with a pin punch and a hammer. As the chains are often large, heavy and positioned closely to other machinery, a pin punch and hammer is often awkward to use in the required close quarters. Other means have been developed to address this problem as described in the patents discussed below.
U.S. Pat. No. 5,463,862, issued to Reisenauer, discloses a breaker for roller chains that includes a rigid frame with a chain receiving opening. A clamp member with an open pin receiving bore is mounted to the rigid frame on one side of the opening for adjustment along an axis. A punch block with a central bore is releasably mounted to the rigid frame on an opposite side of the opening. The punch block is located by a positioner with its central bore substantially coaxial with the axis. The punch block and clamp member include chain link engaging surfaces positioned relative to the opening to releasably clamp a roller chain with a pin thereof aligned with the axis and with the link engaging surfaces in clamping engagement with chain side plates adjacent the pin. A punch pin is slidably mounted within the punch block central bore, with a pin driving end movable through the opening and receivable axially within the pin receiving bore of the clamp member. A headed end of the punch pin is releasably mounted to the ram shaft by a freely rotatable cleat on a saddle that is releasably mounted at the end of a ram shaft. A ram drives the ram shaft and attached punch pin to move along the axis through a prescribed axial stroke to force the pin from the chain.
U.S. Pat. No. 6,453,657, issued to Teravainen is directed to a portable hydraulic press with two opposing plates connected by bolts can be clamped on a conveyor chain that has interference-fit connecting pins between pairs of rectangular plates forming the chain links to assemble or disassemble the chain. Once the press is clamped in place, a hydraulic cylinder of the press is then actuated to force the connecting pin in or out of the chain. If the pin is being pushed out, it passes through a hole in a back plate of the press in order to disassemble or break the chain.
U.S. Patent Application No. 2007/0193247, published for Daniels et al. illustrates a fluid activated connecting pin removal tool that includes a body defining a first cavity adapted to receive a portion of a work piece and a second cavity positioned substantially perpendicular to and intersecting the first cavity. When a fluid activated cylinder is mounted to the body in a first orientation relative to the second cavity, expansion of the fluid activated cylinder results in a piston extending from the cylinder into the first cavity in which the work piece is positioned to exert a force upon a connecting pin connecting portions of the work piece. When the fluid activated cylinder is mounted to the body in a second orientation relative to the second cavity, the secondary cavity serves as a storage compartment for the fluid activated cylinder.
U.S. Pat. No. 6,748,637, issued to Meggiolan disclose a tool for inserting and extracting pins of roller chains, comprising a body having a pair of teeth designed to engage two chain links to be connected or separated by insertion or extraction of a pin. The tool comprises a screw member which can be operated manually and which is provided with a punch designed to co-operate with a pin that is to be inserted or extracted. The tool comprises two retaining elements which can move between an inoperative position, in which the chain links can freely engage and disengage the teeth, and an operative position, in which the teeth block the chain links in a pre-set position with respect to the teeth.
U.S. Pat. No. 5,934,061, issued to Smith is directed an apparatus for assembling and disassembling roller chain and the like is provided. The apparatus includes a base portion made up of a base plate and side plates, a rotatable cam and an interchangeable die set inserted into the base portion which is in contact with the cam. The die set is sized to fit a particular type and size of chain. The particular die set may be designed to punch out connecting pins in a link of the chain. Alternatively, the die set may be for purposes of installing a link plate onto connecting pins or for purposes of deforming the ends of connecting pins during the assembly process.
It is an objective of the present invention to provide a compact, easy-to use system for servicing roller chains. It is a further objective to provide such a system that does not require an external power source. It is a still further objective of the invention to provide a system that can be operated with one hand and that will work in tightly confined locations. Finally, it is an objective of the present invention to provide such apparatus that is durable, inexpensive and simple for the operator to use.
While some of the objectives of the present invention are disclosed in the prior art, none of the inventions found include all of the requirements identified.